Ask an expert: Your Questions about Defibrillators

Have you got questions about defibrillators? Our expert has answers! Claire Greenwood was a cardiac intensive care nurse for fifteen years and is now USL Medical’s product manager for critical care capital. Claire is here to answer some of our burning questions about AEDs (automated external defibrillators), their role in saving lives in the community, and how we can all be ready in an emergency.

1. What is a defibrillator, and how does it work in a cardiac emergency?

A defibrillator is a device that delivers a high energy electric shock to the heart of someone who is in sudden cardiac arrest. This shock is an essential part of trying to save the life of someone who’s in sudden cardiac arrest.
It is important to note that sudden cardiac arrest is different to having a heart attack, which is a blood circulation problem. Sudden cardiac arrest is the sudden loss of all heart activity due to an irregular heart rhythm, breathing also stops.

2. How crucial are defibrillators in a community setting, and what role do they play
in saving lives?

Making AEDs more readily available is literally the difference between life and death for some people. Having an AED available for someone in cardiac arrest can increase their chance of survival by 44%. For every minute without one, chance of survival decreases by 10%. Each year more than 2000 New Zealanders are treated for cardiac arrest outside of the hospital. Fewer than 15% survive.

3. What are the key benefits of having easily accessible defibrillators
in private spaces or community areas?

Early defibrillation along with CPR is the only way to restore a patient’s heart rhythm. Therefore, having AEDs easily accessible, along with other key actions, is vital to their survival. When someone suffers a sudden cardiac arrest outside of the hospital, there’s a chain of events that can significantly improve their chance of survival. This is called the Chain of Survival:
•    Early recognition that a cardiac arrest has occurred, meaning an awareness and understanding the signs.
•    Access to emergency services–dialling 111.
•    Early access to CPR–being ready to act.
•    Early access to defibrillation–knowing the location and how to use the nearest AED.
•    Advanced Care–ambulance services arriving.
•    Post resuscitation treatment in the hospital.
In order to enable a successful chain of survival, accessible AEDs are a must in public and private spaces.

4. Do you need to be a medical professional in order to use a defibrillator?

Modern AEDs, such as the Rescue Sam, are designed to be used by someone with little or no training. These types of automated defibrillators use both visual and voice prompts to guide the user through the emergency, by checking the patient’s heart rhythm and advising when to deliver the shock.

5. Are there any specific locations or types of places where having a defibrillator
is especially important?

Proper placement of AEDs is crucial to ensure quick access and effective response. There are a few elements that indicate good areas to house AEDs: high traffic; high visibility and accessibility; and a proximity to risk areas (meaning areas where people are more likely to suffer sudden cardiac arrest like swimming pools, fitness centres, or sports fields).  
If possible, make the AED available 24/7. This might involve installing a cabinet with a digital code or lock that can be accessed using a code provided by emergency services.
Alongside placing AEDs, providing training to community members in CPR and AED use is vital. Increased awareness about the presence and use of AEDs can save more lives.
Ultimately, the best locations for AEDs will depend on the layout and characteristics of your community. Collaborate with local emergency services, healthcare professionals, and community members to make informed decisions about AED placement.

6. What steps can individuals take to ensure widespread access to defibrillators and proper maintenance?

Maintenance requirements are relatively minimal, including regular checks to ensure that they are functional and have up to date batteries and electrode pads.
Encouraging your community spaces, such as schools, cafes, and clubs to invest in an AED is a good first step. From an individual and small business perspective, ensuring that you and your loved ones are in reach of an AED and investing in one if you aren’t, can be proactive.

7. Are there any misconceptions or myths about defibrillators that you often
come across?

Sure! Here are a few:
AEDs can re-start a stopped heart:
Myth: A common misconception is that AEDs can restart a heart that has stopped beating.
Fact: AEDs are designed to treat specific types of life-threatening heart rhythms, particularly ventricular fibrillation (VF) and ventricular tachycardia (VT). These devices deliver and electric shock to the heart to reset its rhythm, but they do not “restart” a heart that is completely stopped. CPR is also crucial to provide blood flow to the heart and brain until professional medical help arrives.
AEDs are complicated to use:
Myth: Many people believe that using an AED requires advanced medical knowledge.
Fact: AEDs are designed to be user friendly, with voice prompts and visual instructions that guide even untrained individuals through the process. They are designed for anyone to use in an emergency, regardless of medical background.
AEDs can harm a person:
Myth: AEDs can hurt the wrong person.
Fact: AEDs are designed to analyse the patient’s heart rhythm before delivering a shock. If a shock is not needed, the AED will not deliver one. The device’s safety features minimise the risk of accidental shocks to the rescuer, or the person being treated.

8. Could you provide some guidance on how to conduct basic CPR along with using a defibrillator for someone who hasn't received formal training?

•    Check the scene and the person:

Before approaching the person, ensure the area is safe. Gently tap the person and shout, “are you ok?” to check if they are responsive. If there is no response and they are not breathing or not breathing normally, immediately call for emergency help on 111.

•    Start CPR:

Begin CPR with chest compressions to circulate blood throughout the body. Follow these steps:
1.    Position the person on their back on a firm surface.
2.    Place the heel of one hand on the centre of the person’s chest, slightly above the lower half of the sternum (breastbone).
3.    Place your other hand on top of the first hand and interlock your fingers.
4.    Compress the chest hard and fast, at least 5cm deep for adults.
5.    Compress the chest at a rate of 100-120 compressions per minute.
6.    Allow the chest to fully recoil between compressions without lifting your hands off the chest.

•    Use the AED:

If an AED is available, follow these steps to use it:
1.    Turn on the AED by pressing the power button.
2.    Follow the visual and voice prompts provided by the AED.
3.    Attach the AED pads to the persons bare chest as shown on the pictures on the pads.
4.    Make sure no one is touching the person while the AED analyses the heart rhythm.
5.    If the AED advises a shock, make sure no one is in contact with the person and press the shock button as instructed by the AED. Some AEDs deliver the shock automatically.

•    Resume CPR:

After delivering the shock, or if the AED advises against shocking, immediately resume CPR.

•    Continue AED and CPR cycles:

Continue alternating between AED analysis (the AED will prompt every two minutes) and CPR cycles. Follow the AEDs prompts and listen for instructions.

•    Continue until professional help arrives:

Continue using the AED and performing CPR until one of the following:
1.    The person starts showing signs of life, like breathing normally.
2.    Professional medical help arrives.
3.    You are too exhausted to continue.
 
Remember: AEDs are designed to be used by both trained professionals and bystanders. They provide a clear voice and visual instructions to guide you through the process. If you’re unsure, it’s always better to start CPR while waiting for professional medical help and the AED to arrive.